Here at Zacks, we focus on our proven ranking system, which places an emphasis on earnings estimates and estimate revisions, to find winning stocks. But we also understand that investors develop their own strategies, so we are constantly looking at the latest trends in value, growth, and momentum to find strong companies for our readers.Of these, perhaps no stock market trend is more popular than value investing, which is a strategy that has proven to be successful in all sorts of market environments. Value investors use fundamental analysis and traditional valuation metrics to find stocks that they believe are being undervalued by the market at large.Luckily, Zacks has developed its own Style Scores system in an effort to find stocks with specific traits. Value investors will be interested in the system's "Value" category. Stocks with both "A" grades in the Value category and high Zacks Ranks are among the strongest value stocks on the market right now.One company value investors might notice is Tempur Sealy (TPX). TPX is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock has a Forward P/E ratio of 13.04. This compares to its industry's average Forward P/E of 16.64. Over the past 52 weeks, TPX's Forward P/E has been as high as 19.44 and as low as 11.82, with a median of 13.95.TPX is also sporting a PEG ratio of 0.61. This popular figure is similar to the widely-used P/E ratio, but the PEG ratio also considers a company's expected EPS growth rate. TPX's PEG compares to its industry's average PEG of 0.72. Over the past 52 weeks, TPX's PEG has been as high as 1.26 and as low as 0.37, with a median of 0.66.Finally, investors should note that TPX has a P/CF ratio of 13.03. This metric focuses on a firm's operating cash flow and is often used to find stocks that are undervalued based on the strength of their cash outlook. This stock's P/CF looks attractive against its industry's average P/CF of 20.76. Over the past year, TPX's P/CF has been as high as 15.24 and as low as 10.19, with a median of 12.67.These figures are just a handful of the metrics value investors tend to look at, but they help show that Tempur Sealy is likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, TPX feels like a great value stock at the moment. More Stock News: This Is Bigger than the iPhone! It could become the mother of all technological revolutions. Apple sold a mere 1 billion iPhones in 10 years but a new breakthrough is expected to generate more than 77 billion devices by 2025, creating a $1.3 trillion market. Zacks has just released a Special Report that spotlights this fast-emerging phenomenon and 4 tickers for taking advantage of it. If you don't buy now, you may kick yourself in 2022.Click here for the 4 trades >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Tempur Sealy International, Inc. (TPX): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research